1. Field of the Invention
The present invention relates to a temperature controller for a semiconductor device, and more particularly to a temperature controller capable of accurately and quickly controlling the temperature of a semiconductor device.
2. Description of the Prior Art
As is well known in the art, semiconductor devices are widely used in various electronic components and devices such as transistors, integrated circuits, and the like. Many light beam scanners such as scanning recorders and scanning readers for deflecting and scanning a light beam with a light beam deflector employ semiconductor lasers as means for emitting such a scanning light beam.
The semiconductor devices are highly temperature-dependent. It is necessary to effect highly accurate temperature control on certain semiconductor devices such as a semiconductor laser which must be as free as possible from output power changes dependent on temperature variations. Various arrangements are known for controlling the temperature of such a semiconductor device. For example, the semiconductor device to be controlled is attached to a heat-radiating panel to enable the latter to radiate the heat transmitted from the semiconductor device. If desired, a temperature sensor is attached to the heat-radiating panel, and a temperature controlling element such as an electronic cooling device or a heater is coupled to the heat-radiating panel, which is bodily controlled in temperature by the temperature controlling element in response to an output signal from the temperature sensor.
With the aforesaid known arrangement, however, the temperature of the semiconductor device is detected and controlled through the heat-radiating panel by the temperature sensor and the temperature controlling element attached thereto. As a consequence, it takes a certain period of time before the semiconductor device is fully controlled in temperature. Another problem is that it is difficult to effect accurate temperature control because the overall heat-radiating panel has a large heat capacity.